Planning for Ions (for NA61 & LHC)

1. Planning for Ions (for NA61 & LHC) P. Collier /BE

2. Budget Requirements • For the Fragmentation tests (approved by the last RB) • 225 kCHF (+2MY) • to modify the T2 target and the secondary target (will only be done after the 2010 tests) • Calculate the optics of the transfer line • Improve the shielding around the experiment. • Request not yet made by EN in their MTP for 2011. • In order to put any primary beam into the North area • 610kCHF (+2MY) • To provide a new North area interlocks system preventing accidental extraction of (high intensity) protons during Ion operation • A full safety study • Not yet approved (or requested) – main costs to BE • The costs associated with the production of light ions for LHC (and NA61) • Around 460kCHF (+5MY) • Mainly for instrumentation of linac3, but also low-level RF for PS and SPS. • Around 80kCHF for the plasma chamber of the ion source. • 50kCHF for the collaboration with the source in South Africa • Not yet approved (or requested) – main costs to BE • p-Pb Option not discussed here Specific Costs for SPS NA Specific Costs for SPS NA Costs for both LHC and SPS NA

3. Schedule to run with a known species • To set up the complex with a known species for a run in the LHC will require: • 2 weeks in the source/Linac3 – independent of other facilities • 2 weeks in LEIR – independent of other facilities • 2 weeks in PS – taking a cycle in the machine (slight impact on PS users) • 2 weeks in the SPS – adding a cycle in the machine (some impact on NA and CNGS) • 4 weeks of Physics in the LHC • 12 weeks total • To set up the complex with a known species for a NA61 run will require: • 2 weeks in the source/Linac3 – independent of other facilities • 2 weeks in LEIR – independent of other facilities • 2 weeks in PS – taking a cycle in the machine (slight impact on PS users) • 4 weeks in the SPS – adding a cycle in the machine (some impact on NA and CNGS) • 1 week preparation of the extracted beams in the North Area (no North area physics) • 6 weeks of Physics in the SPS (No beam for non Ion Physics in the NA) • 17 weeks total If the same species is used for both programmes then they can run at the same time. The overhead for NA61 operation is therefore just a few weeks extra running of the Ion Chain.

4. Additional Overhead for the first use of a New Species • Optimizing and tuning the source for a new species is complicated and time consuming. • 11 weeks are estimated to be needed to prepare a new species from scratch. • In addition an extra 3 weeks (5 in total) would be needed to set up the new ions in LEIR • Also 1 extra week would be needed in the PS • A nearly identical source is under construction in South Africa. • An MoU is under preparation for a collaboration with iThemba Lab • Under this agreement they would set up their source with the specified ion species and pass to CERN the optimized parameters. • This will remove the 11 weeks above from our schedule – if the construction and preparation of their source is compatible with our schedule.

5. Physics Request (approx) SPS (NA61) LHC • 4-weeks per year is requested. • Assume no LHC run in 2012 • p-Pb is requested for 2015 – but will require additional effort/commissioning in the LHC • I don’t think that LHC has expressed a firm interest in Xenon. • 2010/2011 are tests – not Physics • From 2012, 6 weeks per year requested. • Boron, Argon and Xenon requested. • Boron to be generated by fragmentation. • No interest in Lead. • Physics each year at 6 different energies … 10, 20, 30, 40, 80 & 158 GeV/u

6. Schedule • 2010 and 2011 • No problem since the LHC and Fragmentation tests will both use Pb • Both runs scheduled together • Running time for the ion injectors will therefore be around 12 weeks/year. • 2012 • Assuming that the LHC does not run, but the SPS does • Argon in the SPS for NA61 should be possible • The South African source might not be ready – but the source set-up could be done at CERN (in this case no margin in case of problems). • Running time for the Ion injectors = 21 weeks (+possibly 11 for the source) • 2013 • Pb ions requested for NA61 and LHC (Fragmented beam in the North Area) • Running time for the Ion Injectors = 17 weeks. • 2014 • Pb in the LHC and Xe for NA61 would have to run one after the other. • In addition a new species for NA61 • The Ion chain would therefore have to run 21+12 = 33 weeks • The source would have to be prepared by iThemba

7. Why is running Time Important? • The same Operations Team runs AD and LEIR • This was based on the idea that LEIR would run for a relatively few weeks a year and AD would stop early. • However, AD running time is increasing (28 wk physics + 4 wk setup in 2010) • Up to now LEIR has run for commissioning the ion chain (mainly daytime) • For physics operation it will have to run 24/7. • Extra coverage has been provided by SPS operators in recent years during the commissioning • From the schedules outlined above there should be no great problem until 2014 • In 2014 the running time for the Ion chain will be very hard for the operations team and machine experts to manage. • If there is no Ion run in the SPS in 2012 the Argon run would have to be delayed to 2014 and the schedule extended to allow Xenon in 2015. • This would mean 2 very long years for the ion chain We should come back to the manpower for AD and Ion operation after first experience with Physics in the LHC and in the light of any decision concerning Elena.